Let’s Go Backward—Proofs by Contradiction
Lecture no. 7 from the course: Prove It: The Art of Mathematical Argument
Taught by Professor Bruce H. Edwards | 30 min | Categories: The Great Courses Plus Online Mathematics Courses
Probe the power of one of the most popular techniques for proving theorems—proof by contradiction. Begin by constructing a truth table for the contrapositive. Then work up to Euclid’s famous proof that answers the question: Can the square root of 2 be expressed as a fraction?